Solution : https://service.sap.com/sap/support/notes/1579438 (SAP Service marketplace login required)
Key words :
life reinsurance module - internal - -> basic settings -> maintain extensions, software component fs-ri financial servi, policy -> maintain number range object, release 650 sapk-65008inmsg - sapk-65011inmsg, release 660 sapk-66005inmsg - sapk-66005inmsg, life reinsurance module -> settings, highest existing retro share number, document -> save -> active version, basic substitution rules delivered, highest retro share number